Photovoltaic and spectral properties of tetraphenyloporphyrin and metallotetraphenyloporphyrin dyes

Spectroscopical properties and photocurrent (or photovoltage) of tetraphenyloporphyrins and metallotetraphenyloporphyrins in nematic liquid crystal have been studied. Photoelectric response has been measured in an electrochemical cell made of the semitransparent semiconducting and golden electrodes with porphyrin dyes embedded in liquid crystal. Fluorescence, time-resolved luminescence in microsecond time scale and photoacoustic spectra have also been measured. The competition between radiative, non-radiative processes and charge transfer is discussed. It has been shown that effectivity of porphyrins for photocurrent generation depends on the presence/absence of central metal in the macrocycle of porphyrin skeleton and the kind of metal. The schematic model of the contributions of the dye molecule and semiconducting electrode in the electron transfer process is shown.     

基于EPON智能电能表光通信模块的设计与实现

智能电能表光通信模块的研究,在智能电网建设中发挥着重要作用。通过对EPON(以太网无源光网络)、PLC(电力载波通信)和WiMAX(全球微波互联接入)技术的对比分析,选择EPON作为智能电能表通信接入网技术,并设计了通信流程。基于QCA8829嵌入式芯片,在Redhat Linux 2.6.x开发平台上采用可接入EPON系统的光纤接口技术,实现了智能电能表主站与从站的通信系统。经测试表明,基于EPON智能电表光通信模块实现了智能电网配电侧信息全采集、全覆盖,并使远程电费控制及负载控制到户。     

一种基于CoMP的随机接入方案

提出了一种新的基于协作多点传输和接收（CoMP）技术的多发随机接入流程,并根据 随机接入的目的和业务类型设计了接入优先级,在此基础上设计了一种新的随机接入方案, 对 不同类型的随机接入请求提供不同的接入机制,以保证边缘用户的接入性能和满足不同业务 的QoS需求。仿真结果表明,与LTE标准随机接入方案相比,该方案对系统整体接入性能略有 提高,且大大提高了边缘高优先级用户的接入性能。     

检测DL-苹果酸的高锰酸钾化学发光体系

利用高锰酸钾化学发光体系测定了DL-苹果酸 ,测得该物质的浓度与其对应的化学发光峰值在一定范围内存在较好的线性关系。测定DL-苹果酸的线性范围在1.0×10-6～1.0×10-2mol·L-1;相对标准偏差为1.4%(n=8) ,检出限为1.0×10-9mol·L-1。测定实际苹果汁与饮料 ,结果良好。实验表明 ,该法线性范围宽、重现性好、操作简便。文中还探讨了该体系的自催化属性。     

注射用生物可降解胰岛素纳米微球的制备

共聚物;药剂释放体系;注射用生物可降解胰岛素纳米微球的制备     

基于CoMP传输的分布式异构网络资源分配

摘要：提高无线资源利用效率是缓解日益增长的无线通信需求和有限的可用传输资源之间矛盾的主要途径。基于多点协调（coordinated multipoint,CoMP）传输技术的异构网络在提高频谱效率和能量效率方面具有巨大的潜力,近年来受到学术界和工业界的广泛关注。在研究基于CoMP技术的异构网络资源分配问题的基础上,提出了一种基于交叉熵方法的分布式频谱资源调度算法。仿真实验验证了本文提出方法在系统吞吐量、能量效率以及用户公平性等方面的有效性。     

Bi-directional LSTM based channel estimation in 5G massive MIMO OFDM systems over TDL-C model with Rayleigh fading distribution

In this work, a deep learning (DL)-based massive multiple-input multiple-output (mMIMO) orthogonal frequency division multiplexing (OFDM) system is investigated over the tapped delay line type C (TDL-C) model with a Rayleigh fading distribution at frequencies ranging from 0.5 to 100 GHz. The proposed bi-directional long short-term memory (Bi-LSTM) channel state information (CSI) estimator uses online learning during training and offline learning during the practical implementation phase. The design of the estimator takes into account situations in which prior knowledge of channel statistics is limited and targets excellent performance, even with limited pilot symbols (PS). Three separate loss functions (mean square logarithmic error [MSLE], Huber, and Kullback–Leibler Distance [KLD]) are assessed in three classification layers. The symbol error rate (SER) and outage probability performance of the proposed estimator are evaluated using a number of optimization techniques, such as stochastic gradient descent (SGD), momentum, and the adaptive gradient (AdaGrad) algorithm. The Bi-LSTM-based CSI estimator is trained considering a specific number of PS. It can be readily seen that by incorporating a cyclic prefix (CP), the system becomes more resilient to channel impairments, resulting in a lower SER. Simulations show that the SGD optimization approach and Huber loss function-trained Bi-LSTM-based CSI estimator have the lowest SER and very high estimation accuracy. By using deep neural networks (DNNs), the Bi-LSTM method for CSI estimation achieves a superior channel capacity (in bps/Hz) at 10 dB than long short-term memory (LSTM) and other conventional CSI estimators, such as minimum mean square error (MMSE) and least squares (LS). The simulation results validate the analytical results in the study.     

Surface Engineering of Poly(DL‐lactic acid) by Entrapment of Biomacromolecules

Alginate, chitosan and gelatin were deposited on the surface of PDL‐LA films via an entrapment method. ATR‐FT‐IR, XPS and contact‐angle analyses revealed the formation of stable thin biomacromolecule layers on the PDL‐LA film, thus enhancing the hydrophilicity of the films. Confocal laser scanning microscopy showed the existence of entrapment areas of approximately 10–20 μm in depth. This simple surface‐treatment method may have the potential for many biomedical applications.     

5G双小区协作流动热点补偿研究

在通信用户数密集用户业务总量较多的UMi场景下,无线网络节点较多小区覆盖半径较小,用户在小区间移动导致小区间用户分布不均匀,原有用户数及业务量标准部署的5G异构网络相对稀疏,无法满足用户流动产生热点热时容量需求时,双小区协作流动热点补偿采用异构网络多点协作传输技术对小区进行补热,将处于相同移动状态的多个用户虚拟成一个以中心用户为中心的用户簇,建立3D MIMO流动热点模型,提出在两小区以用户最小传输速率为约束条件,最小化小区基站总功率的优化算法,得出高容量、高速率用户体验的"潮汐效应"解决方案。